Self interacting dark matter

In astrophysics, self-interacting dark matter (SIDM) is a hypothetical form of dark matter consisting of particles with strong self-interactions. This type of dark matter was postulated in 2000 to resolve a number of conflicts between observations and simulations (of collisionless cold dark matter) on the galactic scale and smaller.

Self-interacting dark matter has also been postulated as an explanation for the DAMA annual modulation signal.